/*
 * Copyright (C) 2021 Square, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package app.cash.zipline.gradle

import org.gradle.api.DefaultTask
import org.gradle.api.file.DirectoryProperty
import org.gradle.api.provider.Property
import org.gradle.api.tasks.Input
import org.gradle.api.tasks.InputDirectory
import org.gradle.api.tasks.Optional
import org.gradle.api.tasks.TaskAction
import org.gradle.deployment.internal.DeploymentHandle
import org.gradle.deployment.internal.DeploymentRegistry

abstract class ZiplineServeTask : DefaultTask() {

  @get:InputDirectory
  abstract val inputDir: DirectoryProperty

  @get:Optional
  @get:Input
  abstract val port: Property<Int>

  @TaskAction
  fun task() {
    val deploymentId = "serveZipline"
    val deploymentRegistry = services.get(DeploymentRegistry::class.java)
    val deploymentHandle = deploymentRegistry.get(deploymentId, DeploymentHandle::class.java)
    if (deploymentHandle == null) {
      // First time this task is run, start the server.
      deploymentRegistry.start(
        deploymentId,
        DeploymentRegistry.ChangeBehavior.BLOCK,
        ZiplineDevelopmentServer::class.java,
        inputDir.get(),
        port.orNull ?: 8080,
      )
    } else {
      // On subsequent task runs, just send a websocket message. We trigger this call reflectively
      // because the two instances of this task may be running in different class loaders.
      val method = deploymentHandle::class.java.getMethod("sendReloadToAllWebSockets")
      method.invoke(deploymentHandle)
    }
  }
}
